You might think that everyone will hate Messenger Day, that Facebook has made a big misstep, that it'll likely hurt Messenger's performance - but all of that will bear out in the actual user data.

Many criticized Facebook's most blatant Snapchat rip-off - Instagram Stories - when it launched, but now more than 150 million people use it every day. That's a quarter of Instagram's active user base now spending more time and posting more content within the app - while the app's overall user growth has also increased at a faster rate than at any other time in its history. Safe to say the criticism, in this case, was off target.

Two - Facebook runs large-scale tests of all such additions before a bigger roll out.

Messenger Day is obviously new to the majority of users, but it's been available in Australia and Poland for five months, two nations which, combined, have close to 30 million social media users, a significant test group which has no doubt provided Facebook with a heap of feedback.

If the feedback was negative, if there was a reduction in time spent in the app, if people hated the addition, do you really think Facebook would have given it a wider release?

That's not to say that Facebook is infallible - reports this week, for example, suggest that they've dialed back their emphasis on their Snapchat-clone within WhatsApp - nor does it mean that Messenger Day will be a sure-fire hit, but Facebook have a refined testing process in place. They don't make such decisions on a whim.

They may still make mistakes, but they're fairly educated bets. The fact that Messenger Day is being given a larger release would suggest that those initial tests have produced good results - don't be surprised if Messenger Day sees big adoption in Facebook's coming performance reports.

In line with this, we now have news that Facebook's latest Snapchat-like test, this time within Facebook proper, is also getting an expanded test pool.

And the speed at which they're ramping up testing here could be telling - as noted Facebook started testing Messenger Day in Poland in early October last year, then added Australia two weeks later. The addition of Australia effectively doubled the size of the test - but with Facebook Stories, the sample size is getting much bigger in the second phase. Ireland has around 2.8 million active social media users, whereas Chile, Vietnam and Greece combined have more than 64 million social media actives.

The level of expansion likely suggests that Irish users have responded well to the initial tests, otherwise it's a big risk to take - Facebook hasn't provided any further timeline details or rollout plans, but looking at the numbers here, it does seem that a larger rollout will be coming soon, giving users yet another option for sharing social stories.

And if we do see a wider rollout of Facebook Stories, you can, again, expect to see a lot of criticism - people will say Facebook's gone too far, that there are too many options, but a lot of these criticisms boil down to personal opinion. Of course, personal commentary is largely all we have to go on in the early stages without audience numbers, but without them, we don't know how platform users are actually responding.

The tale is in the data, not in the initial reaction.

What will be most interesting, from a social media marketing perspective, will be first, how popular these new options are among users, but then, how brands can use them.

For Instagram and Messenger Day, we already have some answers (brands can use Instagram Stories but can't use Messenger Day direct), but if we do see a wider rollout of Facebook Stories, will it be available to Pages? You'd suspect it won't, but there'll no doubt be paid ad options in future, and if it does prove popular, and Pages aren't able to use it directly, influencer marketing will continue to rise in significance as a means of spreading your brand message to Stories via individual users.

It's also unclear if and how it might work on the desktop version - though, again it'll likely be the same as Messenger Day, which is not available on the Messenger desktop site.

But regardless of all this, the key consideration to keep in mind is that it's user behavior that dictates the importance of such options - if your audience likes social stories and is active on Instagram Stories or Messenger Day, then that's where you also need to be looking, regardless of whether you personally like the tools or not.

Definitely, it's fun to debate the merits of such tools and options and to consider what they mean for the platforms more generally, but the actual user stats themselves will tell the true tale. Criticism of the format, the layout, the cannibalization of audience - all of this pales in comparison to raw user numbers.

It's worth keeping an open mind to all new tools and platforms as they arrive.